/*
 * Copyright 2002-2018 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.jms.listener.endpoint;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.beans.BeanWrapper;

import javax.jms.Session;
import javax.resource.spi.ResourceAdapter;

/**
 * Default implementation of the {@link JmsActivationSpecFactory} interface.
 * Supports the standard JMS properties as defined by the JCA 1.5 specification,
 * as well as Spring's extended "maxConcurrency" and "prefetchSize" settings
 * through autodetection of well-known vendor-specific provider properties.
 *
 * <p>An ActivationSpec factory is effectively dependent on the concrete
 * JMS provider, e.g. on ActiveMQ. This default implementation simply
 * guesses the ActivationSpec class name from the provider's class name
 * ("ActiveMQResourceAdapter" -> "ActiveMQActivationSpec" in the same package,
 * or "ActivationSpecImpl" in the same package as the ResourceAdapter class),
 * and populates the ActivationSpec properties as suggested by the
 * JCA 1.5 specification (Appendix B). Specify the 'activationSpecClass'
 * property explicitly if these default naming rules do not apply.
 *
 * <p>Note: ActiveMQ, JORAM and WebSphere are supported in terms of extended
 * settings (through the detection of their bean property naming conventions).
 * The default ActivationSpec class detection rules may apply to other
 * JMS providers as well.
 *
 * <p>Thanks to Agim Emruli and Laurie Chan for pointing out WebSphere MQ
 * settings and contributing corresponding tests!
 *
 * @author Juergen Hoeller
 * @see #setActivationSpecClass
 * @since 2.5
 */
public class DefaultJmsActivationSpecFactory extends StandardJmsActivationSpecFactory {

    private static final String RESOURCE_ADAPTER_SUFFIX = "ResourceAdapter";

    private static final String RESOURCE_ADAPTER_IMPL_SUFFIX = "ResourceAdapterImpl";

    private static final String ACTIVATION_SPEC_SUFFIX = "ActivationSpec";

    private static final String ACTIVATION_SPEC_IMPL_SUFFIX = "ActivationSpecImpl";


    /**
     * Logger available to subclasses.
     */
    protected final Log logger = LogFactory.getLog(getClass());


    /**
     * This implementation guesses the ActivationSpec class name from the
     * provider's class name: e.g. "ActiveMQResourceAdapter" ->
     * "ActiveMQActivationSpec" in the same package, or a class named
     * "ActivationSpecImpl" in the same package as the ResourceAdapter class.
     */
    @Override
    protected Class<?> determineActivationSpecClass(ResourceAdapter adapter) {
        String adapterClassName = adapter.getClass().getName();

        if (adapterClassName.endsWith(RESOURCE_ADAPTER_SUFFIX)) {
            // e.g. ActiveMQ
            String providerName =
                    adapterClassName.substring(0, adapterClassName.length() - RESOURCE_ADAPTER_SUFFIX.length());
            String specClassName = providerName + ACTIVATION_SPEC_SUFFIX;
            try {
                return adapter.getClass().getClassLoader().loadClass(specClassName);
            } catch (ClassNotFoundException ex) {
                logger.debug("No default <Provider>ActivationSpec class found: " + specClassName);
            }
        } else if (adapterClassName.endsWith(RESOURCE_ADAPTER_IMPL_SUFFIX)) {
            //e.g. WebSphere
            String providerName =
                    adapterClassName.substring(0, adapterClassName.length() - RESOURCE_ADAPTER_IMPL_SUFFIX.length());
            String specClassName = providerName + ACTIVATION_SPEC_IMPL_SUFFIX;
            try {
                return adapter.getClass().getClassLoader().loadClass(specClassName);
            } catch (ClassNotFoundException ex) {
                logger.debug("No default <Provider>ActivationSpecImpl class found: " + specClassName);
            }
        }

        // e.g. JORAM
        String providerPackage = adapterClassName.substring(0, adapterClassName.lastIndexOf('.') + 1);
        String specClassName = providerPackage + ACTIVATION_SPEC_IMPL_SUFFIX;
        try {
            return adapter.getClass().getClassLoader().loadClass(specClassName);
        } catch (ClassNotFoundException ex) {
            logger.debug("No default ActivationSpecImpl class found in provider package: " + specClassName);
        }

        // ActivationSpecImpl class in "inbound" subpackage (WebSphere MQ 6.0.2.1)
        specClassName = providerPackage + "inbound." + ACTIVATION_SPEC_IMPL_SUFFIX;
        try {
            return adapter.getClass().getClassLoader().loadClass(specClassName);
        } catch (ClassNotFoundException ex) {
            logger.debug("No default ActivationSpecImpl class found in inbound subpackage: " + specClassName);
        }

        throw new IllegalStateException("No ActivationSpec class defined - " +
                "specify the 'activationSpecClass' property or override the 'determineActivationSpecClass' method");
    }

    /**
     * This implementation supports Spring's extended "maxConcurrency"
     * and "prefetchSize" settings through detecting corresponding
     * ActivationSpec properties: "maxSessions"/"maxNumberOfWorks" and
     * "maxMessagesPerSessions"/"maxMessages", respectively
     * (following ActiveMQ's and JORAM's naming conventions).
     */
    @Override
    protected void populateActivationSpecProperties(BeanWrapper bw, JmsActivationSpecConfig config) {
        super.populateActivationSpecProperties(bw, config);
        if (config.getMaxConcurrency() > 0) {
            if (bw.isWritableProperty("maxSessions")) {
                // ActiveMQ
                bw.setPropertyValue("maxSessions", Integer.toString(config.getMaxConcurrency()));
            } else if (bw.isWritableProperty("maxNumberOfWorks")) {
                // JORAM
                bw.setPropertyValue("maxNumberOfWorks", Integer.toString(config.getMaxConcurrency()));
            } else if (bw.isWritableProperty("maxConcurrency")) {
                // WebSphere
                bw.setPropertyValue("maxConcurrency", Integer.toString(config.getMaxConcurrency()));
            }
        }
        if (config.getPrefetchSize() > 0) {
            if (bw.isWritableProperty("maxMessagesPerSessions")) {
                // ActiveMQ
                bw.setPropertyValue("maxMessagesPerSessions", Integer.toString(config.getPrefetchSize()));
            } else if (bw.isWritableProperty("maxMessages")) {
                // JORAM
                bw.setPropertyValue("maxMessages", Integer.toString(config.getPrefetchSize()));
            } else if (bw.isWritableProperty("maxBatchSize")) {
                // WebSphere
                bw.setPropertyValue("maxBatchSize", Integer.toString(config.getPrefetchSize()));
            }
        }
    }

    /**
     * This implementation maps {@code SESSION_TRANSACTED} onto an
     * ActivationSpec property named "useRAManagedTransaction", if available
     * (following ActiveMQ's naming conventions).
     */
    @Override
    protected void applyAcknowledgeMode(BeanWrapper bw, int ackMode) {
        if (ackMode == Session.SESSION_TRANSACTED && bw.isWritableProperty("useRAManagedTransaction")) {
            // ActiveMQ
            bw.setPropertyValue("useRAManagedTransaction", "true");
        } else {
            super.applyAcknowledgeMode(bw, ackMode);
        }
    }

}
